net: fix __dst_negative_advice() race (Linux Linux)

CVE-2024-36971
HIGH 7.8CISA KEV ↗Exploited per ENISA since 2024-08-07

At a glance

Source
NVD
EPSS
EPSS 2.70 % · percentile 86 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: net: fix __dst_negative_advice() race __dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF. RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst). Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order. Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves. Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks. Many thanks to Clement Lecigne for tracking this issue. This old bug became visible after the blamed commit, using UDP sockets.

Weaknesses (CWE)

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCISA-ADP
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < 051c0bde9f0450a2ec3d62a86d2a0d2fad117f13 ; affected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < db0082825037794c5dba9959c9de13ca34cc5e72 ; affected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < 2295a7ef5c8c49241bff769e7826ef2582e532a6 ; affected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < eacb8b195579c174a6d3e12a9690b206eb7f28cf ; affected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < 81dd3c82a456b0015461754be7cb2693991421b4 ; affected a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 < 5af198c387128a9d2ddd620b0f0803564a4d4508
Linux · Linuxaffected 4.6 ; unaffected 0 < 4.6 ; unaffected 4.19.316 ≤ 4.19.* ; unaffected 5.4.278 ≤ 5.4.* ; unaffected 5.10.219 ≤ 5.10.* ; unaffected 5.15.161 ≤ 5.15.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
CISA Known Exploited VulnerabilitiesCC0 1.0
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD